CVE-2023-39969

uthenticode signature validation bypass vulnerability

Description

uthenticode is a small cross-platform library for partially verifying Authenticode digital signatures. Version 1.0.9 of uthenticode hashed the entire file rather than hashing sections by virtual address, in violation of the Authenticode specification. As a result, an attacker could modify code within a binary without changing its Authenticode hash, making it appear valid from uthenticode's perspective. Versions of uthenticode prior to 1.0.9 are not vulnerable to this attack, nor are versions in the 2.x series. By design, uthenticode does not perform full-chain validation. However, the malleability of signature verification introduced in 1.0.9 was an unintended oversight. The 2.x series addresses the vulnerability. Versions prior to 1.0.9 are also not vulnerable, but users are encouraged to upgrade rather than downgrade. There are no workarounds to this vulnerability.

Category

9.0
CVSS
Severity: Critical
CVSS 3.1 •
EPSS 0.10%
Vendor Advisory github.com
Affected: trailofbits uthenticode
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-39969?
CVE-2023-39969 has been scored as a critical severity vulnerability.
How to fix CVE-2023-39969?
To fix CVE-2023-39969, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-39969 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-39969 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-39969?
CVE-2023-39969 affects trailofbits uthenticode.
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